Hilary Mantel won the Booker in 2009 with Wolf Hall.
Mantel becomes first novelist to win both Man Booker and Costa prizes.
The unstoppable Hilary Mantel last night added another award to her astonishing haul of major literary prizes when judges unanimously named Bring up the Bodies the 2012 Costa book of the year.
Mantel became the first novelist to win both the Man Booker and the Costa prize when a nine-strong judging panel took less than an hour to decide that her thrilling, gripping and bloody second instalment of her Tudor trilogy was a clear winner.
It was perhaps the least surprising result in the prize's history. The chair of judges, Dame Jenni Murray, said: "One book simply stood head and shoulders, more than head and shoulders ... on stilts, above the rest. We had a really good discussion, like being at a high powered book club and I said, 'OK, let's have a vote on Bring up the Bodies' and every hand went up."
Murray admitted it was a tricky prize to judge as one is choosing between different genres. There are five category winners bidding to win the GBP30,000 main prize - that means pitting poetry against biography, first novel, children's book and novel. That did not make it difficult, though. "I'd like to tell you there was blood on the carpet, there wasn't. There was absolute unanimity."
Some commentators have suggested that the one book which did not need any helping hand in terms of sales was Bring up the Bodies, having sold 240,000 hardback copies already - miles ahead of the other four which have not sold more than 30,000 together.
But Murray said that was not what the prize was about - it was completely irrelevant. "These prizes are about 'What is the best book, what is the most enjoyable book? If I were to go away from here tonight and choose a book I wanted to read again, what would it be?'
"Everybody knew that there was just one book that we know has had lots of prizes but we couldn't allow the number of times it has been lauded to affect our decision."
Murray said everything they read was "immensely pleasurable". Many observers had hoped a graphic work might become the first overall Costa winner, with Mary and Bryan Talbot's graphic memoir Dotter of her Father's Eyes flying the biography flag.
The other contenders were Francesca Segal's first novel, The Innocents; Kathleen Jamie's poetry collection The Overhaul, and Sally Gardner's children's book Maggot Moon.
Since Mantel brought out Wolf Hall, which won the 2009 Booker prize, she has been like a literary steamroller. We can expect to see a dramatisation of the two novels on the BBC this year and next year the Royal Shakespeare Company is to put on stage versions adapted by Mike Poulton.
Bring Up the Bodies is a much more condensed read than Wolf Hall, tackling in enveloping detail the downfall of Anne Boleyn beginning in September 1535, just after Thomas More's execution to May 1536 when she was publicly executed.
Murray said Mantel's prose was poetic and beautiful. "It is so set in its time, you know exactly where you are and who you are with but it is also incredibly modern. Her analysis of the politics is so modern.
"Everybody found that there were things that just stuck in their minds that they would think about for a very long time. I have no doubt that I want to go back to it."
Murray said she had read it twice now, on her Kindle and in book form. Publishers should not worry - the book experience was much more pleasurable.
Mantel, 60, was the winner from a shortlist notable for being almost all female (Bryan Talbot illustrated while his wife Mary wrote). Murray said she had nothing to do with that, but added: "It was a real joy for me to see five women's names there."
Bring up the Bodies has been lavishly praised by most critics although the Sunday Times' Andrew Holgate was a rare voice of dissent, writing that there were too many characters and it was too mired in the historical detail. "The result is a book that is curiously flat and leaden, and one whose central ambition, to explain its chief subject, is frustratingly unfulfilled."
Although some might have been daunted by the four-and-a-half-page dramatis personae at the beginning of the novel, most readers delighted in it.
When Antony Hegarty won the Mercury prize for music in 2005, he memorably remarked: "It's like a contest between an orange and a spaceship and a potted plant and a spoon." The same goes for the Costa. Last year the judging chair, Geordie Greig, said it was like comparing "bananas with chicken curry".
The judging panel for this year's prize was appropriately diverse. It consisted of actors Jenny Agutter and Sophie Ward, the broadcaster Katie Derham, poet Daljit Nagra, novelist DJ Taylor, comedian Mark Watson, writer Marcus Sedgwick and the author Wendy Holden.
The prize was announced at a ceremony in central London. Most people in the room immediately tweeted the result. Mantel did not. Her Twitter account reads simply: "Writes a great deal, tweets never."